AWS Troubleshooting Guide : How to Quickly Fix Common AWS Issues

A structured troubleshooting process helps you:

• Reduce downtime
• Identify root causes faster
• Prevent repeated issues
• mprove cloud performance and reliability

Symptoms:

• Slow connectivity
• Failed API calls
• Instances unreachable from the internet

Possible Causes:

• Misconfigured security groups or network ACLs
• Incorrect routing tables
• Internet Gateway or NAT Gateway issues

Fix:

• Check security group and NACL rules to allow required traffic
• Verify route tables and ensure they point to the correct gateway
• Confirm that instances in private subnets have proper NAT configurations
• Use VPC Reachability Analyzer for AWS network troubleshooting

Symptoms:

• Domain not resolving
• Internal services unreachable by name
• Delays in propagation

Possible Causes:

• Incorrect Route 53 records
• TTL settings too long
• Outdated DNS cache

Fix:

• Verify hosted zone records and ensure mappings are correct
• Reduce TTL values for faster propagation
• Clear DNS cache on local machines or applications
• Use Route 53 Health Checks to ensure domain availability

Symptoms:

• Instances can’t communicate across subnets or VPCs
• Peering connection not working

Possible Causes:

• Misconfigured VPC peering routes
• Overlapping CIDR blocks
• Disabled DNS resolution between VPCs

Fix:

• Confirm routing tables for each VPC include peering routes
• Ensure CIDR blocks do not overlap
• Enable “DNS resolution” and “DNS hostnames” options within your VPC
• Use VPC Flow Logs to monitor rejected traffic and diagnose root causes

Symptoms:

• Users unable to connect to contact center
• Calls dropping or failing to route
• Latency or voice quality problems

Possible Causes:

• Network latency or bandwidth issues
• Misconfigured contact flows
• IAM permission errors

Fix:

• Test connection speeds to AWS Connect endpoints.
• Validate IAM policies and roles used by Connect
• Review contact flow setup for missing or broken links
• Use AWS CloudWatch metrics for performance insights

Symptoms:

• SSH/RDP access denied
• Timeout while connecting

Possible Causes:

• Wrong key pair
• Blocked ports
• Stopped or rebooting instances

Fix:

• Verify the correct key pair is associated with the instance
• Open necessary ports (22 for SSH, 3389 for RDP) in security groups
• Check the instance status and ensure it’s running
• Use AWS Systems Manager Session Manager for secure access without open ports

Symptoms:

• “Request limit exceeded” or “Instance limit reached” messages

Possible Causes:

• Service quotas (limits) reached for EC2, Lambda, or other resources

Fix:

• Check your AWS Service Quotas dashboard
• Request a quota increase where needed
• Implement resource cleanup automation to remove unused items

Symptoms:

• Access denied errors
• Failed API operations

Possible Causes:

• Missing IAM permissions
• Misconfigured trust relationships

Fix:

• Review IAM policies attached to users and roles
• Test permissions with the IAM Policy Simulator
• Follow the principle of least privilege for better security

1. Set Up Monitoring and Alerts

Use AWS CloudWatch, CloudTrail, and Config to detect anomalies before they become problems.

2. Automate Diagnostics

Automate routine checks using AWS Lambda scripts or AWS Systems Manager Automation runbooks.

3. Document Your Architecture

Keep an updated diagram of your VPCs, subnets, and dependencies. This makes troubleshooting faster.

4. Enable Logging Everywhere

Turn on logs for EC2, VPC Flow, CloudTrail, and Route 53 — they provide critical data during issue analysis.

5. Establish a Troubleshooting Playbook

Document recurring aws network issues, aws dns issues, or aws connect issues with their solutions. This builds team efficiency.

6. Perform Regular Health Checks

Use AWS Trusted Advisor and Health Dashboard to catch potential failures early.

Need quick help with an AWS issue?

Get in touch with eDelta Corporation today for expert AWS troubleshooting and network recovery support.